QUIC: fixed ngx_http_test_reading() for QUIC streams.

Previously this function generated an error trying to figure out if client shut
down the write end of the connection.  The reason for this error was that a
QUIC stream has no socket descriptor.  However checking for eof is not the
right thing to do for an HTTP/3 QUIC stream since HTTP/3 clients are expected
to shut down the write end of the stream after sending the request.

Now the function handles QUIC streams separately.  It checks if c->read->error
is set.  The error flags for c->read and c->write are now set for all streams
when closing the QUIC connection instead of setting the pending_eof flag.

src/event/ngx_event_quic.c

@@ -1460,7 +1460,7 @@ ngx_quic_close_timer_handler(ngx_event_t *ev)
 static ngx_int_t
 ngx_quic_close_streams(ngx_connection_t *c, ngx_quic_connection_t *qc)
 {
-    ngx_event_t        *rev;
+    ngx_event_t        *rev, *wev;
     ngx_rbtree_t       *tree;
     ngx_rbtree_node_t  *node;
     ngx_quic_stream_t  *qs;
@@ -1486,8 +1486,12 @@ ngx_quic_close_streams(ngx_connection_t *c, ngx_quic_connection_t *qc)
         qs = (ngx_quic_stream_t *) node;
 
         rev = qs->c->read;
+        rev->error = 1;
         rev->ready = 1;
-        rev->pending_eof = 1;
+
+        wev = qs->c->write;
+        wev->error = 1;
+        wev->ready = 1;
 
         ngx_post_event(rev, &ngx_posted_events);
 
@@ -4005,6 +4009,10 @@ ngx_quic_stream_recv(ngx_connection_t *c, u_char *buf, size_t size)
     qc = pc->quic;
     rev = c->read;
 
+    if (rev->error) {
+        return NGX_ERROR;
+    }
+
     ngx_log_debug3(NGX_LOG_DEBUG_EVENT, c->log, 0,
                    "quic stream id 0x%xL recv: eof:%d, avail:%z",
                    qs->id, rev->pending_eof, b->last - b->pos);
@@ -4093,6 +4101,7 @@ ngx_quic_stream_send(ngx_connection_t *c, u_char *buf, size_t size)
     u_char                 *p, *end;
     size_t                  fsize, limit, n, len;
     uint64_t                sent, unacked;
+    ngx_event_t            *wev;
     ngx_connection_t       *pc;
     ngx_quic_frame_t       *frame;
     ngx_quic_stream_t      *qs;
@@ -4101,8 +4110,9 @@ ngx_quic_stream_send(ngx_connection_t *c, u_char *buf, size_t size)
     qs = c->qs;
     pc = qs->parent;
     qc = pc->quic;
+    wev = c->write;
 
-    if (qc->closing) {
+    if (wev->error) {
         return NGX_ERROR;
     }
 

src/http/ngx_http_request.c

@@ -3022,6 +3022,19 @@ ngx_http_test_reading(ngx_http_request_t *r)
 
 #endif
 
+#if (NGX_HTTP_QUIC)
+
+    if (c->qs) {
+        if (c->read->error) {
+            err = 0;
+            goto closed;
+        }
+
+        return;
+    }
+
+#endif
+
 #if (NGX_HAVE_KQUEUE)
 
     if (ngx_event_flags & NGX_USE_KQUEUE_EVENT) {